Welding-torch.



I. U. MARLIN.

WELDING TORCH.

APPLICATION TILED MAY 15. I914.

Patented May 29,1917.

' fication.

ISAAC U. MAR-BIN, OF SHREVEPORT, LOUISIANA. ASSIGNOR, BY MESNEASSIGNMENTS, TO GEORGE T. CUNNINGHAM AND LOUIS T. CUNNINGHAM, BOTH OFSHREVEPORT,

LOUISIANA.

To all whom it may concern:

Be it known that I, ISAAC U. MARLIN, a citizen of the United States,residing Shreveport, in the parish of Caddo and State of- Louisiana,have invented certain new and useful Improvements in Welding- Torches,of which the following is a speci- The object of my invention is toprovide a welding torch of the oxy-acetylene type so constructedthat thegases may be fed to the torch at a comparatively low pressure and theproper mixture will be obtained with the gases in the desired proportionand thoroughly. intermingled thus preventing burning of the metal beingworked.

A further object is to so construct .the torch that there can be no'back-fire and the formation of soot and scales within the tip of thetorch is'prevented.

With other objects in view, which will be referred to, my inventionconsists in the peculiar combination and novel arrange ment of parts,such as will be hereinafter more fully described in connection with .theaccompanying drawing andmore particularly pointed outin the appendedclaims.

In the drawing t I Figure 1 is a longitudinal sectional View through thetorch to more clearly illustrate. the parts and theoperation.

Fig. 2 is a sectional View through the combining tube. I

ig. 3 1s a smilar view through the oxygen supply-nipple.-

In a Welding torch of the oxy-acetylene type if too great a proportionof oxygen is contained in the mixture as discharged from the torch tipto the flame, this excess of oxygen combines with the metal and themetal is said to be burned, in case iron is being worked upon, theoxygen would combine to form the comparatively fragile sub stance ferricoxid and the life and tenacity of the metalwould be destroyed, on theother hand, if an excess of acetylene gas be present, the torch" is aptto back-fire and soot and scales are formed in the burner tip.

The torch structure comprises the butt 1 which has the hollow handle 2extending therefrom and the oxygen inlet 3 and the acetylene inlet 4 areconnected with this butt 1. The butt 1 within the handle 2 has ascrew-threaded projection 5 provided and this projection '5 is cored outat its center at Specification of Letters Patent.

Patented May 29, 1917.

Application filed May 15,1914. Serial No. 838,828.

6 and is provided with internal screw threads. A passage 7 is providedthrough the butt 1 from the oxygen supply to the cored-out portion 6 anda similar passage 8 is provided from the acetylene inlet to open oil theface of the projection 5 in the marglnal portion, surrounding thecored-out section of this projection. An oxygen nipple has its lowerscrew-threaded end 10 received in the cored-out orifice 6, this nipplebeing tapered fromits base to'its outer end and provided with a passage11 which establishes communication from the passage 7 to' the outlet ofthis nipple; A combining tube 11 is secured on the screw threads of theprojecting portion 5 to surround the nipple 9 and the side walls of thiscombining tube are constricted as at 12 to conform very closely. to theconverging side of the nipple. I j

A mixing tube'l3 is connected by tube union 14 with the handle of thetorch and this mixing tube is extended a sufficient distance that theheat from the'flame will not betransmitted to the handle 2. A shortsection of tube 15 is secured in the union 14 and is connected in theouter end of the combining tube 11 in such a manner thatthe mixing tubeis substantially a continuation of the combining tube. At the outer endof the/mixing tube 13,'the torch head let is secured and this torch headis preferably so constructed that the tip 15 secured in the free endthereof is at an angle to the extent of the mixing tube. A'valve seat 16is provided and ball-check valve 17 is positioned to fit down withinthis valve seat and to be held normally closed by a coil spring 18 toprevent back-fire through the torch tip and head to the mixing tube.Cut-off valves 19 and 20 are provided in the oxygen and acetylene supplylines to control and regulate the supply of each of these gasespermitted to flow to the torch.

In use, oxygen is permitted to How through the supply 3 through passage7 and passage 11 to the outlet of the oxygen nipple and acetylene ispermitted to pass from the supply 4: through the valve 20 and throughpassage 8 into the combining tube the point of greatest restriction, asiphonic and is caused 5 and through to flow wieh fiche oxygen into themlxlng tube Where the two gases are circulated sogether e116.

more thoroughly intemningledh the course of the oxygen is inelieateci.by the -1ene gas is indicate& by

full-liueerrow while the course of the ecee the {EOMJQXI'EILQ err-ow.When flue pressure of the combined gases in the mixing tube 13 becomessuifieiently great the bell check 1'? will be raised from the valve seat16 ageinst the tension of the spring 18 and this combined.eXy-eeeeylea-e gas will be permitted to pass out thz'ough the burner tip15- to the flame. Any decrease of the pressure of the gas flowingthrough the mixing tube will permit the ball check to be again see'uediand the $036 11 will prevented from back-firing into the mixing tube,

From the foregoing, it will be seen that I have providecl Welding torchin which the two gases oxygen and acetylene use-e at the flame arethoroughly eombine i eui time teymingled before being permiizeeoi "passto the flame em} thus oumiug of etel beingworked. is prevented nd Kt-1fiae tendency "m the of so scales in the burner furioher W izeirch asshown and '7 all 5 is ebsoluec i Jhi ie I heme herein specific of 1 I vA cuemeer, c0 AOUSQLJ the combining tube, and e, To uee'teoi with mecombining wjoe 3, A. Welding eoreh comprising; an e supply nipple, ecombining tube sen around

